Conveyor Belt Alignment Switch,
Type AFA, AFAX • Model M2
IF 959
Installation & Maintenance Information
SAVE THESE INSTRUCTIONS FOR FUTURE REFERENCE
APPLICATION
Type AFA, AFAX conveyor belt alignment switches are used to protect
bulk handling conveyor belts from damage due to abnormal belt
misalignment or run-off due to excessive speed, uneven load, leveling,
breakage, and/or other problems.
When mounted in proper position on either side of conveyor belt, the
operating arm will rotate in a counter-clockwise direction when
contacted by the belt. Contact sets 1 and 2 and 5 and 6 will open within
a 7° to 15° travel of the operating arm and remain in this state for all
further counter-clockwise rotation. Contact sets 3 and 4 and 7 and 8
will close within a 23° to 31° travel of the operating arm and remain in
this state for all further counter-clockwise rotation (see Figure 3 on page
2 for a diagram of the contact arrangement). Over-travel of 85° is built
in so that a severe run off cannot damage the switch mechanism. The
operating arm is spring loaded and will automatically return the switch to
normal position when belt interference is removed.
Type AFA conveyor belt alignment switches may be used in Class II,
Groups E, F, G and Class III hazardous (classified) locations as defined
by the National Electrical Code® (NEC).
Type AFAX conveyor belt alignment switches may be used in Class I,
Groups C, D; Class II, Groups E, F, G; and Class III hazardous
(classified) locations as defined by the National Electrical Code (NEC).
Type AFAX is UL Listed Enclosure Types 3, 4, and 12.
Type AFA, AFAX switches should be installed, inspected and
maintained by qualified and competent personnel.
Horizontal Mounting
INSTALLATION
The following table is offered as the suggested maximum torque for the
threaded items, and is to be used as a guide only.
WARNING
Hammers or prying tools must not be allowed to damage the flat
joint surfaces. Do not handle covers roughly, or place them on
surfaces that might damage or scratch the flat joint surfaces.
Compromising flat joint surfaces can result in injury to personnel
or damage to equipment.
Table 1
Bolt Size
Max. Torque (N-m)
Max. Torque (lb.-ft.)
5/16"-18
15 N-m
11 lb.-ft.
1/4"-28
11 N-m
8 lb.-ft.
WARNING
Be sure all power is turned OFF before and during installation
and maintenance. Failure to turn off power can result in injury to
personnel or damage to equipment.
WARNING
Type AFAX units are designed to meet Class I, Groups C, D;
Class II, Groups E, F, G; and Class III hazardous (classified)
location requirements of the National Electrical Code. These
units are supplied with machined metal-to metal joints for switch
housing and access covers. Do not use gaskets. Clean both
flat joint surfaces of body, switch housing and cover before
closing. Dirt or foreign material must not accumulate on flat joint
surfaces. Surfaces must seat fully against each other to provide
a proper explosionproof joint. Clean both flat joint surfaces of
body and cover before closing. To avoid the possibilities of an
explosion, oxidation and corrosion, do not use gasoline or similar
solvents.
1.
Disassemble unit by removing access covers and switch housing
from body.
2.
Mount body in horizontal or vertical position as shown in Figures 1
and 2. Use bolts or screws through two (2) 7/16 inch diameter
mounting lug holes.
Note: 1-½ inch center mounting hole spacing permits attachment of
body to the web of a standard 3 inch angle iron.
CAUTION
Operating arm rotates in counter-clockwise direction only. For
switch units on opposite side of belt, mount unit in opposite
direction.
3.
Install conduit into hubs as required and pull all necessary wires into
body.
® National Electrical Code is a Registered Trademark of the National Fire Protection Association.
IF 959 • 11/12
Copyright © 2012, Cooper Industries, Inc.
Page 1
•
•
•
CAUTION
Hazardous location information specifying class and group
listing is marked on the nameplate of each enclosure.
All unused conduit openings must be plugged. Plug must
engage a minimum of five (5) full threads and be a minimum
of 1/8 inch thick.
Conduit sealing fittings may be required to be installed in each
attached conduit run to comply with the latest edition of
National Electrical Code plus any other applicable code.
Contact
Arrangement
Diagram
Cat. #
2
1
N.C.
2 normally
open
2 normally
closed
N.O.
3
4
6
5
2 pole:
AFA20/AFAX20-M2
N.C.
4.
5.
N.O.
With type AFA Series only, make sure gasket is in place to mate
with flange of switch housing.
Determine opening in body that will be used to mount the switch
housing. Any one of the three (3) openings may be used as
determined by the mounting position of the body and the orientation
of the operating arm to the belt. Using this opening, connect the
DPDT switch to the line wires following your system wiring pattern in
compliance with the latest edition of the National Electrical Code
plus any other applicable code. See Figure 3 for switch contact
arrangement.
6.
Mount switch housing assembly to body with four (4) screws
provided, orienting operating arm in correct position. Assemble
roller to required height. Lock in height by tightening Allen head
screw at the end of the shaft. Tighten Allen head screw to proper
torque value listed in Table 1 on previous page.
7.
Test wiring for correctness with continuity checks and for unwanted
grounds with insulation resistance tester.
8.
Replace access covers on all unused openings. With AFA style
only, make sure that gaskets are properly seated when they are
required. Make sure all bolts are securely tightened to proper
torque value listed in Table 1 on previous page.
7
Figure 3 • Switch Contact Arrangement
Switches Rated at 7-1/2 Amperes, 600VAC
Note: For single phase applications, wire only contacts 1 through 4
WARNING
Type AFAX units are designed to meet Class I, Groups C, D;
Class II, Groups E, F, G; and Class III hazardous (classified)
location requirements of the National Electrical Code. These
units are supplied with machined metal-to metal joints for switch
housing and access covers. Do not use gaskets. Clean both
flat joint surfaces of body, switch housing and cover before
closing. Dirt or foreign material must not accumulate on flat joint
surfaces. Surfaces must seat fully against each other to provide
a proper explosionproof joint. Clean both flat joint surfaces of
body and cover before closing. To avoid the possibilities of an
explosion, oxidation and corrosion, do not use gasoline or similar
solvents.
9.
8
Figure 4 • Switch
Check operating arm by pushing in direction indicated in Figure 1
and Figure 2 on next page. Arm should move through full overtravel without binding.
IF 959 • 11/12
Copyright © 2012, Cooper Industries, Inc.
Page 2
IF 959 • 11/12
Copyright © 2012, Cooper Industries, Inc.
Page 3
MAINTENANCE
WARNING
Be sure all power is turned OFF before and during installation
and maintenance. Failure to turn off power can result in injury to
personnel or damage to equipment.
1.
Frequent inspection should be made. A schedule for maintenance
checks should be determined by the environment and frequency of
use. It is recommended that it should be at least once a year.
2.
If necessary to open enclosure for inspection or service, refer to
cautionary statement on nameplate before removing cover.
3.
Perform visual, electrical, and mechanical checks on all components
on a regular basis.
•
Visually check for undue heating evidenced by discoloration of wires
or other components, damaged or worn parts, or leakage evidenced
by water or corrosion in the interior.
•
Electrically check to make sure that all connections are clean and
tight.
•
Mechanically check that all parts are properly assembled, and
operating mechanisms move freely.
WARNING
If any part of the switch components appears to be broken or
damaged, DISCONTINUE USE IMMEDIATELY.
Replace or properly repair the item before continuing service.
Failure to comply may result in personnel injury or damage to
equipment.
CAUTION
Clean both flat joint surfaces of body and cover before closing.
Dirt or foreign material must not accumulate on flat joint
surfaces. Surfaces must seat fully against each other to provide
a proper explosionproof joint. Compromising flat joint surfaces
can result in injury to personnel or damage to equipment.
4.
Make sure all cover bolts are securely tightened to proper torque
value listed in Table 1 on first page.
5.
Cooper Crouse-Hinds recommends an Electrical Preventative
Maintenance program as described in the National Fire Protection
Association Bulletin NFPA No. 70B.
All statements, technical information and recommendations contained herein are based on information and tests we believe to be
reliable. The accuracy or completeness thereof are not guaranteed. In accordance with Crouse-Hinds "Terms and Conditions of Sale",
and since conditions of use are outside our control, the purchaser should determine the suitability of the product for his intended use
and assumes all risk and liability whatsoever in connection therewith.
Cooper Industries Inc.
Crouse-Hinds Division
PO Box 4999, Syracuse, New York 13221 • U.S.A.
Copyright© 2012, Cooper Industries, Inc.
IF 959
Revision 5
Revised 11/12
Supersedes 09/06